By reasonably generating Gaussian AN at the transmitter, the detection of the Eve can be deteriorated, so as to further improve the security performance of the system [1]}. [2]} projected AN onto the null-space of the desired channel to interfere unknown eavesdropper. Although NSP scheme ensures the high security performance in high SNR region, the beamformer design for AN has not been further expored to further improve the security performance of SSM. The authors in [3]} proposed a novel ratio optimization algorithm which reduced computational overhead and achieved near-optimal safety performance.
